Method of using removable cleat system

ABSTRACT

A removable cleat for a shoe is described. The cleat includes a ground-engaging structure for engaging the ground. An attachment structure is for removably attaching the cleat to the footwear. The attachment structure has a vertical axis, a base to which the top of the ground-engaging member is attached, and multiple extensions projecting radially outward from the base. The extensions are adapted for insertion into a cleat receptacle in the shoe to engage a receptacle attachment structure within the receptacle, so that when the cleat is attached to the receptacle, each cleat extension will be securely engaged above a receptacle restraining ledge.

This is a continuation of application Ser. No. 09/641,117, filed on Aug.17, 2000, which is a division of application Ser. No. 09/208,180, filedon Dec. 9, 1998, now U.S. Pat. No. 6,108,944, which is acontinuation-in-part of application Ser. No. 09/062,037, filed on Apr.17, 1998, now U.S. Pat. No. 6,151,805, which is a continuation-in-partof application Ser. No. 08/774,585, filed on Dec. 23, 1996, now U.S.Pat. No. 5,768,809.

Provisional application No. 60/010,099, filed on Jan. 17, 1996.

FIELD OF THE INVENTION

This invention relates to the mounting of traction gear on the bottom offootwear, in particular, athletic footwear.

BACKGROUND ART

Conventional traction gear presently in use employ an attachment meansconsisting of screwing the traction gear into the mated receivingreceptacle in the bottom of the footwear. Using this screw-typeattachment method is especially laborious when one takes into accountthat a typical golf shoe, for instance, has eleven cleats; as a result,replacing the cleats on a pair of golf shoes entails unscrewingtwenty-two cleats and screwing on twenty-two cleats, where each act ofunscrewing or screwing entails several turns, typically two and one-halftimes, for each cleat.

An example of a typical prior-art cleat is in U.S. Pat. No. 4,723,366(hereinafter the '366 (hereinafter the '366 cleat), which patent isincorporated herein by reference. This patent describes a cleat whichincludes a metal stud infrastructure at the core of the cleat, theinfrastructure having a vertical axis and two ends, a screw portion at afirst end for engagement with a receptacle within a shoe, a ground endfor tractive engagement with the ground, and a broad flange between thescrew and head portions and extending radially outward from the verticalaxis; a plastic skirt is molded directly upon the flange portion to forma unitary reinforced radial support member of the cleat. Installation ofthe '366 cleat consists of screwing it into a mated receptacle in thebottom of athletic footwear.

Although some prior-art references show cleat-attachment systems thatrequire less than a full turn, or they require a snap-on arrangement tolock the cleat in place, it appears none of these systems have foundwide acceptance amongst users because of shortcomings in stability,ease-of-use, receptacle size and ease-of manufacture. For instance, inU.S. Pat. No. 4,633,600 to Dassler, a cleat attachment system isdisclosed in which a snap ring socket is utilized to affix a cleat tothe bottom of a shoe.

In U.S. Pat. No. 3,267,593 to Turner, a cleat attachment system isdisclosed wherein the top of a cleat spike has two extensions forming arough T-shape out of the spike, where the spike is inserted into a matedreceptacle having two grooves to receive the extensions. Upon completeinsertion of the spike into a receptacle, the spike is turned until theextensions drop into receiving grooves at the top of the receptacle; aretaining ring is then slid onto the mid-section of the spike, this ringapparently preventing the spike from unseating the extensions from thegrooves.

Similarly, in German Patent Application Nos. DE3134817A1 toSportartikelfabrik Karl Uhl GmbH, and DE3423363A1 to GebrüderGoldschmidt Baubeschläge GmbH, another T-spike design is disclosed inwhich internal to the mated receptacle are ramping means for engagingand retaining the spike extensions. In the former, a rough interiorsurface catches the extensions, while in the latter, a sloping interiorengages the extensions.

U.S. Pat. No. 4,492,047 to Arff, discloses another T-shape spike inwhich the skirt is deformed during insertion. Insertion of the spikecauses the extensions to go up a ramp and then down a ramp, pulling thespike into the receptacle, and leaving the extensions in a holding area.The skirt is deformed so as to result in a pressure against the socket,the pressure apparently holding the spike from accidentally travelingback up the ramp towards removal.

In U.S. Pat. No. 4,035,934 to Hrivnak, another T-shape spike isdisclosed in which the spike column has two indentations. Duringinstallation, two spring arms, each positioned perpendicular to thesurface of the shoe and parallel to the spike, are pressed in duringinsertion of the spike, and spring back out to press against theindentations upon complete insertion. Removal of this spike is achievedwith a U-shaped tool which slides into the spike receptacle and pushesin the spring arms, thus freeing the spike for removal.

SUMMARY

A representative embodiment of the present invention includes a methodof installing a removable cleat to the sole of a shoe. The methodincludes providing a cleat having (1) a ground-engaging structure forengaging the ground; and (2) an attachment structure for removablyattaching the cleat to the footwear. The attachment structure has avertical axis, a base to which the top of the ground-engaging member isattached, and a plurality of extensions attached to the base. Areceptacle is provided for receiving and holding the cleat, thereceptacle being mounted in the sole of a shoe. The receptacle has (1) awall defining a cavity between a receptacle top and a receptacle bottom,wherein portions of the wall extend radially inward toward a centralvertical axis of the receptacle so as to define: (i) a plurality ofinclines within the cavity, and (ii) a plurality of protuberances withinthe cavity, each proturbence extending radially inward toward thevertical axis further than the compressible inclines: (2) a restrainingledge attached to the receptacle bottom and extending into the cavity soas to prevent downward movement of an installed cleat; and (3) anopening in the restraining ledge having at least three equi-distantlyspaced radially projecting lobes that extend radially outward from thecentral vertical axis of the receptacle. The cleat extensions areinserted through the receptacle opening into the receptacle cavity.Then, the extensions are engaged above the restraining ledges so thatthe cleat is securely attached to the receptacle so as to resistrotational movement of the cleat.

In a further embodiment, each cleat extension may have a radial end andan angled indentation located towards the radial end, and the act ofengaging may include engaging each angled indentation with an incline.The plurality of cleat extensions may be equidistantly spaced. Also, theplurality of cleat extensions may lie in a plane perpendicular to thevertical axis of the attachment structure. The cleat may further includea skirt located between the top of the ground-engaging structure and thebottom of the attachment structure base, the skirt extending radiallyoutward beyond the radial ends of the extensions so that when the cleatis attached to the receptacle, the skirt covers the opening in therestraining ledge.

The skirt may include a plurality of openings on the ground-engagingstructure side of the skirt so that a cleat wrench may be inserted intothe skirt openings to maneuver the cleat. Each incline may have arelatively gradual front ascent portion and a relatively steep backdescent portion. Engaging the extensions may include securing eachextension between an incline and a protuberance so as to resistrotational movement of the cleat.

Another representative embodiment includes a removable cleat for a shoe.The cleat includes a ground-engaging structure for engaging the ground;and an attachment structure for removably attaching the cleat to thefootwear. The attachment structure has a vertical axis, a base to whichthe top of the ground-engaging member is attached, and a plurality ofextensions projecting radially outward from the base. The extensions areadapted for insertion into a cleat receptacle in the shoe to engage areceptacle attachment structure within the receptacle, so that when thecleat is attached to the receptacle, each cleat extension will besecurely engaged above a receptacle restraining ledge.

In a further such embodiment, the attachment structure engaged by thecleat extensions includes an incline and a protuberance for each cleatextension, arranged so that when the cleat is attached to thereceptacle, each cleat extension is secured between an incline and aprotuberance so as to resist rotational movement of the cleat. Eachincline may include a relatively gradual front ascent portion and arelatively steep back descent portion. Each protuberance may extendradially inward toward the vertical axis of the attachment structurefurther than the compressible incline. Each extension may have a radialend and an angled indentation located towards the radial end, the angledindentation being adapted to engage a corresponding incline when thecleat is attached to the receptacle.

The plurality of cleat extensions may be equidistantly spaced. Theplurality of cleat extensions may lie in a plane perpendicular to thevertical axis of the attachment structure. The cleat may further includea skirt located between the top of the ground-engaging structure and thebottom of the attachment structure base, the skirt extending radiallyoutward beyond the radial ends of the extensions so that when the cleatis attached to the receptacle, the skirt covers the receptacle.

The skirt may have a plurality of openings on the ground-engagingstructure side of the skirt so that a cleat wrench may be inserted intothe skirt openings to maneuver the cleat.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings are intended to provide a better understanding ofthe present invention, but they are in no way intended to limit thescope of the invention.

FIG. 1 is a side view of a cleat according to one embodiment of theinvention.

FIG. 2 is a top view of the cleat of FIG. 1, showing the shape of thelobes to be inserted into a mated receptacle in the bottom of athleticfootwear.

FIG. 3 is another side view of the cleat of FIG. 1.

FIG. 4 is a bottom view of the cleat of FIG. 1.

FIG. 5 is a bottom view of a receptacle that may receive the FIG. 1cleat.

FIG. 6 is a top section view of the FIG. 5 receptacle wherein the toplayer of the receptacle has been removed.

FIG. 7 is a side vertical section of the receptacle of FIG. 6.

FIG. 8 is a top view of the FIG. 6 receptacle wherein the top layer hasnot been removed.

FIG. 9A is a perspective right side view of a cleat according to apreferred embodiment of the invention.

FIG. 9B is a perspective top view of the FIG. 9A cleat.

FIG. 9C is a perspective front view of the FIG. 9A cleat.

FIG. 9D is a perspective left view of the FIG. 9A cleat.

FIG. 10 is a top view of the cleat of FIG. 9A, showing the shape of thelobes to be inserted into a mated receptacle in the bottom of athleticfootwear.

FIG. 11 is a another side view of the cleat of FIG. 9A.

FIG. 12A is a top section view of a the receptacle for receiving thecleat of FIG. 9A, wherein the top layer off the receptacle has beenremoved.

FIG. 12B is a perspective bottom view of the FIG. 12A receptacle.

FIG. 13 is a side vertical section of the receptacle of FIG. 12A.

FIG. 14 is a bottom view of a cover for the FIG. 12A receptacle.

FIG. 15 is a side view of FIG. 14 cover.

FIG. 16 is a partial view of a FIG. 9A cleat inserted into a FIG. 12Areceptacle.

FIG. 17 is a bottom view of the FIG. 9A receptacle.

FIG. 18 is a top view of an unassembled receptacle for receiving theFIG. 9A cleat.

FIG. 19 is a bottom view of the FIG. 18 receptacle.

FIG. 20 is a section view of the FIG. 18 receptacle.

FIG. 21 is a side view of a cleat according to a preferred embodiment ofthe invention.

FIG. 22 is a side view of a cleat according to a preferred embodiment ofthe invention showing an alternative ground-engaging “soft” golf spike.

FIG. 23 is a top view of a cleat similar to FIG. 21 showing the top ofthe cleat connector.

FIG. 24 is a perspective top view of the cleat of FIG. 21 in areceptacle with the top cover removed.

FIG. 25 is a top view of a cleat connector of the type shown in FIG. 23,with the addition of semi-circular dust covers.

FIG. 26 is a perspective top view of the cleat connector of FIG. 25.

FIG. 27 is a perspective bottom view of a preferred embodiment of areceptacle for receiving the cleat connector of FIG. 25.

FIG. 28 is an inverted side view of a cleat using the cleat connector ofFIG. 25.

FIG. 29 is a perspective bottom view of an alternative receptacle havinga center cone in the top cover.

DETAILED DESCRIPTION

The invention comprises a system for allowing the quick attachment andrelease of a wide variety of traction gear. FIG. 1 shows that in oneembodiment of the invention, the attachment system would be used toattach cleats, such as those disclosed in U.S. Pat. No. 4,723,366, tothe underside of athletic footwear a cleat installed in the bottom of ashoe using the present invention, when viewed from the bottom, has asimilar appearance to the preferred embodiment of the inventiondisclosed herein. Evident in FIG. 1 are the bottom side 17 and top side16 of the plastic skirt 15, the ground-engaging head portion 10 of thecleat, a base 13 to which the plastic skirt and ground-engaging portionare attached and a retaining member 20, which in this case is a base 13with three rounded extensions 22, all of which are positioned around acentral axis 28. In a preferred embodiment of the invention, the top 16of the skirt 15 is slightly concave, and the bottom 17 of the skirt 15is somewhat convex.

FIG. 2 shows the topside 16 of the cleat skirt 15 and the retainingmember 20, which has a roughly triangular shape with indentations 26.The extensions 22 of the retaining member 20 are used in conjunctionwith components inside the receptacle, shown as item 30 in FIG. 5, forlocking in place a properly inserted retaining member 20. Locking inplace occurs after inserting the retaining member 20 into a matedreceptacle opening 40 as shown in FIG. 5 and FIG. 6, and torqueing theretaining member. The extensions 22 are attached to the base 13 (shownin FIG. 1), and together the extensions and the base form the retainingmember 20. In a preferred embodiment of the invention, a completedcleat, comprising the retaining member 20 and traction gear, is made outof plastic with a metal core used to reinforce the structure. Althoughthe invention could be made entirely out of metal, it is preferable thatthe cleat be made partially of plastic and partially of metal. When theretaining member is plastic, the retaining member may be integrallyformed with a plastic skirt of a golf cleat with a core, preferablymetal, extending through the retaining member and the traction gear toform the ground-engaging head portion 10 shown in FIG. 1.

In a preferred embodiment of the invention, upon insertion of theretaining member 20 into a receptacle, the angled surface 24 (shown inFIG. 1) of the extensions 22 allows for a tighter fit of the retainingmember 20 into the receptacle 40 (shown in FIG. 5). The tight connectionnot only serves to give a stable connection between the shoe andtraction gear, but also serves to keep moisture and debris out of theattachment system.

FIG. 3 is another view showing the structure and proportion of theretaining member 20 as attached to traction gear 21. FIGS. 2 and 3 showthat in a preferred embodiment of the invention, the extension 22 form abroad retaining member 20, and the base 13 is cylindrical andconcentrically disposed around the center axis 28; the base 13 isattached to the extensions 22 and the traction gear 21.

FIG. 4, a bottom view of the FIG. 1 cleat, shows that, in a preferredembodiment of the invention, cleats do not have to be redesigned beyondmodifying the retaining member 20 (shown in FIG. 1), and thatconventional cleat designs are intended to be used in conjunction withthe new retaining member; once a cleat is installed, the change in theretaining system is not apparent. A standard golf-cleat wrench maybe-used to engage the traction gear through use of the wrench holes 18.

FIG. 5 is a bottom view of a receptacle 30 that may receive the FIG. 1cleat, showing the receptacle opening 40, with indentations 44 along itsperimeter for accepting the retaining member extensions 22 (shown inFIG. 1). FIG. 5 also shows the ledges 46 that while serving to form theshape of the opening 40, also serve to hold the extensions 22 within thereceptacle. Although preferred embodiments of the invention include asingle receptacle opening 40, alternate embodiments of the system couldhave a receptacle with separate openings for receiving extensions.

FIG. 6 is a section view of FIG. 5 where the top layer of the receptaclehas been removed to show the inner-cavity structure for receiving theretaining member 20 (shown in FIG. 1). Within the cavity, formed allwall portion 50, there are several cantilevered fingers 51, or springarms, that are designed to grip and hold an installed retaining member.When a retaining member is inserted into the indentations 44 andtwisted, the twisting action causes a protruding edge of an extension 22(shown in FIG. 1) to push into and bend the finger 51 to allow theextension to be turned past the location of the finger. Once theprotruding edge of an extension passes the location of the finger, thefinger springs back to nearly its original shape, so that surface 53rests against the perimeter of the extension 22. This allows the cleatto be removed, but only be exerting sufficient force to bend the finger51 away from the surface of the extension 22, an arrangement requiringmuch greater torque than that required during installation of theretaining member. In one embodiment, the fingers are elongated in shape,with surface 53 forming a curved tip to the finger. FIG. 6 also showsbumps 55 which serve as a means for preventing a retaining member frombeing turned too far. In a preferred embodiment, the cleat should not beturned more than about 60°. Coincident with the fingers 51 locking intoplace, the protruding edge of an extension is blocked from furthermovement by the bumps 55, and the entire retaining system is preventedfrom falling out of the receptacle by ledges 46. FIG. 6 also shows onemethod of attaching the receptacle to the underside of footwear by theuse of mounting holes 57.

Spacing within the receptacle may be designed such that duringinstallation of a cleat, the cavity 40 in which the extension is turnedgradually narrows to compress and securely hold the cleat in place.Preferably the spacing is consistent or more gradual than the angledsurface, so that the angled surfaces 24 (shown in FIG. 1) of theextension 22 being pressed against the ledges 46 cause the fit to betight. In addition, having three extensions parallel to the cleat skirtmakes for a more secure, base for a cleat.

FIG. 7 is a vertical section of a portion of the embodiment of thereceptacle of FIG. 6. This view shows the ledge 46 formed by the bottomlayer 45 of the receptacle and the wall portion 50 that defines thecavity within the receptacle. This view also shows the slight rise 48which forms a lip at the receptacle opening so that the edge of aninstalled cleat's skirt may overlap the lip. The lip helps hold thecleat in place and makes it more resistant to lateral forces while thecleat is in use.

FIG. 8, which is the FIG. 6 receptacle where the top layer has not beenremoved, is a view from the top of the receptacle 30 in accordance witha preferred embodiment of the invention. This view shows the top side 67of the mounting holes for attaching the receptacle.

FIGS. 9A-9D, 10 and 11 show a preferred embodiment of a cleat having thesame basic characteristics and structural concerns of the FIGS. 1, 2,and 3 embodiments discussed herein above. Evident in FIG. 9A are thebottom side 17b and top side 16b of the plastic skirt 15b, theground-engaging head portion 10b of the cleat, a base 13b to which theplastic skirt and ground-engaging portion are attached and a retainingmember 20b, which in this case is a base 13b with three roundedextensions 22b, the extensions having an angled surface 24b and beingpositioned around a central axis 28b. FIGS. 9B-9D are respectively theperspective top, front, and left view of the FIG. 9A cleat.

Evident in FIG. 10 are the corresponding topside 16b of the cleat skirt15b and the retaining member 20b, with indentations 26b. The extensions22b of the retaining member 20b are used in conjunction with componentsinside the receptacle 84 of FIG. 12A, for locking in place a properlyinserted retaining member 20b. Locking in place occurs after insertingthe retaining member 20b into a mated receptacle opening 40b shown inFIG. 12A, and torqueing the retaining member. As with the FIG. 1embodiment, upon inserting the retaining member 20b into a receptacle84, the angled surface 24b (shown in FIG. 9A) of the extensions 22bforces a gradual compression of the retaining member 20b as it isinserted into the receptacle cavity 40b, resulting in a tight connectiongiving stability while also serving to keep moisture and debris out ofthe attachment system.

Also evident in the FIG. 10 embodiment is a modification to the FIG. 2embodiment, where the extensions 22 of FIG. 2 are modified to include anindentation 70 that further enhances the invention's resistivity tounlocking and its unintentional removal through normal use. Increasedresistivity is effected by an interlocking of a cantilevered finger 74(shown in FIG. 16) with the indentation 70. The cantilevered finger 74corresponds to the cantilevered finger 51 of the FIG. 6 embodiment, inwhich the cantilevered finger 51 has been thickened to afford a greaterresistivity to unintentional unlocking. Further, upon complete insertionof the retaining member 20b into an appropriate receptacle 84 (shown inFIG. 12A), the end portion 90 of the cantilevered finger 74 rests withinthe indentation 70. Consequently, removal of the cleat requires greatertorque than that required to install the cleat.

FIG. 11 is another view showing the structure and proportion of theretaining member 20b as attached to traction gear 21b, indicating thelocation of indentation 70, as well as showing that the placement of theretaining member 20b and base 13b is concentrically disposed around thecenter axis 28b.

FIG. 12A is a section view of a preferred embodiment of a receptacle forreceiving the cleat of FIGS. 9A-9D, 10 and 11, where the top layer ofthe receptacle 84 has been removed to show the inner-cavity structurefor receiving-the retaining member 20b (shown in FIG. 9A). FIG. 12Bshows a perspective view of the FIG. 12A receptacle. As with the FIG. 6embodiment, included within the cavity, formed by wall portion 78, areseveral cantilevered fingers 74 designed to grip and hold an installedretaining member 20b. When a retaining member is inserted and twisted,the twisting action causes a protruding edge of an extension 22b to pushinto and bend the finger 74 to allow the extension to be turned past thelocation of the finger. Once the protruding edge of an extension passesthe location of the finger 74, the finger springs back to nearly itsoriginal shape, so that surface 90 contacts the perimeter of theextension 22b. As described herein above, when the surface 90 contactsextension 22b, there is an interlocking of cantilevered finger 74 withthe indentation 70 (shown in FIG. 10). This allows the cleat to beremoved, but only by exerting sufficient force to disengage and bendfinger 74 away from indentation 70 and the surface of the extension 22b,an arrangement requiring much greater torque than that required duringinstallation of the retaining member. As with the FIG. 6 embodiment, thefingers are preferably elongated in shape, surface 90 forms a curved tipto the finger, and bumps 55b serve as a means for preventing a retainingmember from being turned too far during insertion.

Also evident in the FIG. 12A receptacle is another preferred embodimentfor attaching the receptacle 84 to the underside of footwear by the useof a mounting slot 80. In this embodiment, the perimeter 100 of thereceptacle 84 comprises three flanges disposed around the receptacleopening 40b. In preferred embodiments, within each flange 82 of theperimeter are two slots 80 for mounting the receptacle 84 to footwear.Mounting of the receptacle is by methods known in the prior art, and mayinclude forming sole material around the slots, or inserting a pin orother object through the slot to effectively nail the receptacle to aninner-sole of a shoe, and then forming the outer-sole material aroundthe receptacle so affixed. The slots 80 are separated by apre-determined distance and are preferably curved to conform to thecurvature of the flange 82 in which the slot 80 is set. Also shown arethree openings 88 to allow for attaching a receptacle cover 96 (shown inFIG. 14) to the receptacle 84.

FIG. 13 is a vertical section of a portion of the embodiment of thereceptacle of FIG. 12A. The FIG. 13 embodiment has a ridge 76 has beenadded in the bottom layer 86 of the wall portion 78 of the receptacle.In this preferred embodiment, the ridge 76 is located upon the downwardside of the receptacle and helps assure mold seal-off. Sealing off themold helps prevent sole material from the outsole molding process fromaccidentally spilling in over the bottom-end of the receptacle duringproduction. (The receptacle and outsole are preferably moldedground-side up.) In addition, by adding ridge 76 to the basic design ofFIG. 6, the structure of the FIG. 6 receptacle is strengthened, makingit less susceptible to torques, distortions, or other forces. Thisresults in better retention of the receptacle within the sole ofathletic footwear.

FIG. 14 shows a receptacle cover 96 having three holes 92 correspondingto the three openings 88 shown in FIG. 12. In preferred embodiments, thereceptacle cover is designed to attach to and seal the top end of thereceptacle 84 of FIG. 12A, so that during molding of a shoe sole aroundthe receptacle, the sole material does not seep under the top edge ofthe receptacle and fill its cavity. In addition, at the center of thecover 96 is a dome 94. This dome hangs downward from the top of thereceptacle, into the receptacle cavity for receiving a retaining member20b (shown in FIG. 9A).

FIG. 15 shows a side view of the FIG. 14 cover, indicating the extent ofthe dome 94 with respect to the rest of the cover's proportions. Thedome forms a cavity 98 between a sole of a shoe and the top of thereceptacle 84 (shown in FIG. 12A). In preferred embodiments, duringmanufacture of a shoe sole, in addition to sole material being moldedaround the receptacles, sole material is also allowed to fill in thecavity 98. Consequently, as a retaining member 20b (shown in FIG. 9A) isinserted into a proper receptacle, the insertion forces a compression ofthe dome which in turn compresses the sole material filling the dome.The dome 94 serves two purposes. First, when the retaining member 20b oftraction gear is fully installed within a receptacle 84 (shown in FIG.12A), the compression of the dome results in a downward pressure uponthe extension 22b from the dome trying to reexpand into its originalshape. Second, when one tries to remove the traction gear from thereceptacle 84, the re-expansion of the sole material helps push theretaining member away from the sole, thus aiding in the removal ofattached gear.

In preferred embodiments, the extensions for the attachment system aremolded using conventional molding processes. Preferably, themolding-process uses mold components having expandable cavities, thesecavities allowing for undercuts to be molded without the use of sideactions or slides. The receptacle may be molded using conventionalmolding processes, where the receptacles are preferably produced on ahorizontal or vertical press and, with the aid of precision mold designand building, are formed in a manner wellknown in the art.

In preferred embodiments of the invention, during manufacture, thereceptacle portion with the top cover attached is placed in an outsolemold, and the ground surface part of a shoe is then molded. The moldingprocess is preferably one of injection or compression molding. Theparticular location of each receptacle within the mold depends on theintended use of the shoe and the design of the shoe's shape. Duringmanufacture of the outsole of one embodiment of the invention, moldsupport-braces may be used to help ensure no deformation of thereceptacles during the molding of the sole. Preferably, thesupport-braces are negatives of the receptacle's shape such that when abrace is inserted into a receptacle, the receptacle 84 and pin holes 88(shown in FIG. 12A) are temporarily sealed off to prevent sole materialfrom filling in the receptacle cavity 40b and pin holes 88. These pinsmay also be used to help orient and position the receptacle so that solematerial flows up to and not beyond the ridge 76 (shown in FIG. 13) thatis visible on the ground side of the receptacle. Once the outsole ismolded, a second material may be molded or cemented to the outsole, andalso cemented to the upper portion of the shoe. In this embodiment, theoutsole and second material combination form a completed sole having theembedded receptacles.

In some embodiments, the shoe sole may be formed of light-weightmaterials such as EVA or foam. In such embodiments, the sole materialmay be insufficiently strong to hold a receptacle firmly in place.Consequently, in preferred embodiments, a support plate may be added tothe sole structure, wherein the receptacles are attached to the plate atthe desired locations, and the sole is formed around the attachedreceptacles. Such plates may also be used for heel support for footwearhaving light-weight heels; similarly, for heel-plates, support-pins mayalso be used to help-prevent heel receptacle deformation.

FIG. 16 is a partial view of a FIG. 9A cleat inserted into a FIG. 12Areceptacle. Shown is a magnified view of the tip 90 of a cantileveredfinger 74 at rest in indentation 70 of retaining member 20b. Asdescribed herein above, after installation of a cleat into a receptacle,the torque required to dislodge the cantilevered finger 74 from theindentation 70 is much greater than that required during installation.

FIG. 17, a bottom view of the FIG. 9A cleat, shows that in thisembodiment of the invention, a three-pronged wrench is inserted into thethree wrench holes 110 used to remove the cleat. Use of athree-wrench-hole design gives greater stability during insertion andremoval of a cleat, and allows greater torque to be applied, withoutslipping out of the holes, during such insertion and removal.

FIG. 18 is a top view of an alternate embodiment where a modified FIG.14 cover is attached to the FIG. 12A receptacle through a flexibleattachment region 120. In this embodiment, the receptacle 84 and cover96 may be integrally formed of a single portion of production material,and simultaneously formed from a single mold. Before insertion of thisembodiment of the receptacle into a shoe sole, the cover is flippedclosed to cover the top of the receptacle. The FIG. 14 cover is modifiedto include two cover flanges 122 which, when the cover is closed, restin-between two of the receptacle flanges 82. The cover flanges 122 alsohave slots 124, which in addition to the receptacle slots 80 describedherein above, are used for mounting the FIG. 18 combined receptacle andcover to the underside of footwear.

FIG. 19 is a bottom view of the FIG. 18 embodiment, showing the ridge 76(see FIG. 13 herein above) which helps prevent sole material from theoutsole molding process from accidentally spilling in over thebottom-end of the receptacle opening 40b with attached FIG. 14 coverhaving the features as disclosed herein above for FIG. 12A and FIG. 14.

FIG. 20 is a top section view of FIG. 18, showing the relationshipbetween the extent of the dome 94 and the receptacle 84. Also shown isthe region defined by portions 126, 128 for receiving the cover flange122 when the cover is closed over the receptacle 84.

FIG. 21 shows a side view of an alternative embodiment of a cleat havingsome of the same basic characteristics of the FIGS. 1, 2, and 3embodiments discussed herein above. Evident in FIG. 21 are a bottom 201of a plastic skirt 203, and a top 205 with receptacles 207 for a cleatwrench. The cleat also has a ground-engaging spike 209 and a base 211 towhich the skirt 203 and the spike 209 are attached. FIG. 22 is a sideview of another cleat with a cleat connector similar to FIG. 21 showingan alternative ground-engaging “soft” golf spike 225. FIG. 23 is a topview of the cleat connector of the cleats in FIGS. 21 and 22 showingretaining member 213, which in this case is the base 211 with threethermoplastic extensions 215 projecting radially outward in a directionperpendicular to a vertical axis 210 of the base 211 in FIG. 21. Eachextension 215 has a front side 217 approximately parallel to a radialmidline 218 of the extension 215 and which extends from a radial end 220of the extension 215 back towards the vertical axis 210 of the base 211.Each extension 215 also has a back side 219, roughly parallel to andsubstantially shorter than the front side 217; the back side 219 is alsocloser to the midline 218 of the extension 215 than the front side 217.The back side 219 extends back from the radial end of the extension 220,partway to the base 210 until it joins another surface 221 which issubstantially perpendicular to the radial midline of the extension 218,so as to form an L-shaped indentation 222. In a preferred embodiment,the extensions 215 all lie in the same plane, and each extension 215 isequidistant from the adjacent extension.

FIG. 24 is a perspective top view of a preferred embodiment of areceptacle 251 for receiving the cleats of FIGS. 21, 22, and 23 with thetop cover removed to show the inner-cavity structure for receiving theretaining member, 213 in FIG. 23. Within a cavity 253, formed by wallportion 255, are several protuberances 257 designed to grip and hold aninstalled retaining member 213. When a retaining member 213 is insertedand twisted, the twisting action rotates the front side 217 of anextension 215 past a protuberance 257 so that the radial end 220 of theextension 215 compresses the protuberance 257, allowing the extension215 to turn past the protuberance 257. The extension 215 can continue torotate until the front side 217 of the extension 215 engages a stoppingwall portion 259 of the cavity 253. The receptacle 250 is designed sowhen the front side 217 of an extension 215 engages a stopping wallportion 259 of the cavity 253, the protuberance 257 springs back tonearly its original shape and snugly engages the L-shaped indentation222 on the back side 219 of the extension 215. Each extension 215 of aninstalled cleat, therefore, is firmly held in place between a stoppingwall 259 and a protuberance 257 so that the retaining member 213 issecurely attached to the receptacle 250.

Removal of the cleat requires rotation in the opposite direction frominstallation. In a preferred embodiment, the protuberances 257 and theradial ends 220 of the extensions 215 are shaped so that rotation of thecleat in the removing direction requires much greater torque than thatrequired during installation. For example, the radial ends 220 of theextension 215 may be tapered on the front side, 223 in FIG. 23, so thatthe radial end more easily rides over and compresses the protuberanceduring installation. Without a taper on the back side 224 of the radialend of the extension 215, substantially greater force is required forthe radial end 220 to ride over and compresses the protuberance 257 whenrotation is in the removing direction. Alternatively, the protuberances257, rather than the extensions 215, may be tapered to allow easierrotation in the installation direction and require greater force forrotation in the removing direction.

FIG. 25 is a top view of a cleat connector 260 of the type shown in FIG.23, with the addition of semi-circular dust covers 261 between eachextension 215. Of course, the cleat connector 260 may be placed on topof a wide variety of surface engaging structures including both surfacepenetrating structures and non-surface penetrating structures. FIG. 26is a perspective top view of the cleat connector 260 of FIG. 25, andFIG. 27 is a perspective top view of a preferred embodiment of areceptacle 262 for receiving the cleat connector 260 of FIG. 25. Toinstall the cleat, the connector extensions 215 are inserted into thereceptacle's semicircular openings 263. The cleat is rotated into placeto engage the structure of the connector 260 with the internal structureof the receptacle 262 as described above with respect to FIGS. 23 and24. This also rotates the dust covers 261 towards the receptacleopenings 263. As the connector 260 locks into place in the receptacle262, the dust covers 261 settle snugly into the receptacle openings 263to seal the openings 263 so as to prevent the entry of debris from theground into the receptacle 262.

As shown in FIG. 28, the dust covers 261 may have an incline so that asthe connector 260 rotates into place in the receptacle 262, the leadingedge 264 of the dust cover 261 is lower, or closer to the base of theconnector 260 that is the trailing edge 265 of the dust cover 261. As aresult, as the cleat is rotated, the dust cover 261 initially rotateseasily over the opening 263 of the receptacle 262. Before the structureof the connector 260 locks into engagement with the internal structureof the receptacle 262, the higher trailing edge 265 of the dust cover261 becomes compressed by the edge of the opening 263 of the receptacle262 increasing the amount of force required to rotate the cleat. Just asthe structure of the connector 260 locks into engagement with theinternal structure of the receptacle 262, the trailing edge 265 of thedust cover 261 clears the edge of the opening 263 of the receptacle 262.This releases the compression of the trailing edge 265 of the dust cover261 which springs down into the opening 263 of the receptacle 262. Thus,the vertical face of the trailing edge 265 of the dust cover 261 fitsagainst the edge of the opening 263 of the receptacle 262 so as to forma secondary lock in addition to the primary lock of the structure of theconnector 260 in engagement with the internal structure of thereceptacle 262. In addition to sealing against the entry of debris intothe receptacle 262, the secondary lock formed by, the dust covers 261 inengagement with the opening 263 of the receptacle 262, providesadditional resistance against the undesired unlocking rotation of theinstalled cleat in high torque environments such as with baseballcleats.

FIG. 27 also shows a receptacle 262 with a receptacle cover 266 having acover spring 267 which extends into a receptacle cavity defined by thereceptacle openings 263. The receptacle spring 267 performs twofunctions similar to that of the dome 94 in FIGS. 14 and 15. First, whena cleat connector 260 is installed so as to engage the structure of thereceptacle 262, the receptacle spring 267 is compressed and therebyexerts a downward pressure on the cleat connector 260 which increasesthe contacting force between the connector 260 and the receptacle 262.Second, when the cleat is rotated for removal from the receptacle 262(e.g., for replacement), the receptacle spring supplies an ejectingforce on the cleat connector 260 which aids in disengaging the cleatconnector 260 from the receptacle 262.

These functions do not necessarily require the use of a dome 94 as inFIGS. 14 and 15, or a spring 267 as m FIG. 27. FIG. 29 shows areceptacle cover 268 having a center cone 269. The cone 269 performs thesame function as the previously discussed dome 94 and spring 267. Inaddition, the size and strength of the cone 269 may be relativelysubstantial when the cleat connector 260 contains a similarly shapedmating depression 270, shown in FIGS. 25 and 26.

It should be realized that while the various preferred embodiments ofcleat receptacles differ in the complexity of their specific structures,this does not significantly restrict the materials which may be used tofabricate such receptacles. All or part of a receptacle may befabricated from metal. Alternatively, all or part of receptacle may befabricated from a synthetic material such as plastic or nylon. Metaloffers great strength, but with relatively great weight. Syntheticmaterials may be relatively lighter, while somewhat less strong thanmetal. Either metal or synthetic materials may, however, be employedsatisfactorily.

In the preceding description and following claims, the term “cleat” isconsistently used, however, no distinction is intended to be createdbetween cleats and spikes, nor should any be inferred. In addition,while preferred embodiments have been described in which a cleat may beremovably attached to a shoe using the described connectors andreceptacles, the use of such connectors and receptacles is not limitedto attaching cleats to shoes, but may be generally employed as aremovably attachable connector system in other applications whichrequire the attachment of one mechanical structure to another.Similarly, it is of course apparent that the present invention is notlimited to the detailed description set forth above. Various changes andmodifications of this invention as described will be apparent to thoseskilled in the art without departing from the spirit and scope of thisinvention as defined in the following claims.

1. A method of installing a removable cleat to the sole of a shoe, themethod comprising: providing a cleat having: a ground-engaging structurefor engaging the ground; and an attachment structure for removablyattaching the cleat to the footwear, the attachment structure having avertical axis, a base to which the top of the ground-engaging structureis attached, and a plurality of extensions attached to the base;providing a receptacle for receiving and holding the cleat, thereceptacle being mounted in the sole of a shoe, the receptacle having: awall defining a cavity between a receptacle top and a receptacle bottom,wherein portions of the wall extend radially inward toward a centralvertical axis of the receptacle so as to define: (i) a plurality ofinclines within the cavity, and (ii) a plurality of protuberances withinthe cavity, each protuberance extending radially inward toward thevertical axis further than the inclines; a restraining ledge attached tothe receptacle bottom and extending into the cavity so as to preventdownward movement of an installed cleat; and an opening in therestraining ledge having at least three equidistantly spaced radiallyprojecting lobes that extend radially outward from the central verticalaxis of the receptacle; and inserting the cleat extensions through thereceptacle opening into the receptacle cavity; and engaging theextensions above the restraining ledges so that the cleat is securelyattached to the receptacle so as to resist rotational movement of thecleat.
 2. A method according to claim 1, wherein each cleat extensionhas a radial end and an angled indentation located towards the radialend, and the act of engaging includes engaging each angled indentationwith an incline.
 3. A method according to claim 1, wherein the pluralityof cleat extensions are equidistantly spaced.
 4. A method according toclaim 1, wherein the plurality of cleat extensions lie in a planeperpendicular to the vertical axis of the attachment structure.
 5. Amethod according to claim 1, wherein the cleat further comprises a skirtlocated between the top of the ground-engaging structure and the bottomof the attachment structure base, the skirt extending radially outwardbeyond the radial ends of the extensions so that when the cleat isattached to the receptacle, the skirt covers the opening in therestraining ledge.
 6. A method according to claim 5, wherein the skirthas a plurality of openings on the ground-engaging structure side of theskirt so that a cleat wrench may be inserted into the skirt openings tomaneuver the cleat.
 7. A method according to claim 1, wherein eachincline has a relatively gradual front ascent portion and a relativelysteep back descent portion.
 8. A method according to claim 1, whereinengaging the extensions includes securing each extension between anincline and a protuberance so as to resist rotational movement of thecleat.
 9. A removable cleat for a shoe comprising: a ground-engagingstructure for engaging the ground; and an attachment structure forremovably attaching the ground-engaging structure to a cleat receptaclein a shoe, the receptacle including: a wall defining a cavity between areceptacle fop and a receptacle bottom, wherein portions of the wallextend radially inward toward a central vertical axis of the receptacleso as to define: (i) a plurality of inclines within the cavity, and (ii)a plurality of protuberances within the cavity, each protuberanceextending radially inward toward the vertical axis further than theinclines; a restraining ledge attached to the receptacle bottom andextending into the cavity so as to prevent downward movement of aninstalled cleat; and an opening in the restraining ledge having at leastthree equidistantly spaced radially projecting lobes that extendradially outward from the vertical axis of the receptacle; and whereinthe attachment structure is adapted for secure attachment to thereceptacle so as to resist rotational movement.
 10. A removable cleataccording to claim 9, wherein the attachment structure includes aplurality of cleat extensions arranged so that when the cleat isattached to the receptacle, each cleat extension is secured between anincline and a protuberance so as to resist rotational movement of thecleat.
 11. A removable cleat according to claim 10, wherein each cleatextension has a radial end and an angled indentation located towards theradial end, the angled indentation being adapted to engage acorresponding incline when the cleat is attached to the receptacle. 12.A removable cleat according to claim 10, wherein the plurality of cleatextensions lie in a plane perpendicular to a vertical axis of theattachment structure.
 13. A removable cleat according to claim 9,wherein the cleat further comprises a skirt located between the top ofthe ground-engaging structure and the bottom of the attachmentstructure, the skirt extending radially outward so that when the cleatis attached to the receptacle, the skirt covers the receptacle.
 14. Aremovable cleat according to claim 13, wherein the skirt has a pluralityof openings on the ground-engaging structure side of the skirt so that acleat wrench may be inserted into the skirt openings to maneuver thecleat.
 15. An attachment system, comprising: A. a receptacle, thereceptacle having an opening and a member engaging structure includingat least three receptacle projections; and B. a member, rotationallyattachable to the receptacle, having a vertical axis with first andsecond ends, including at the first end, an attachment structureincluding at least three member projections, each member projectionhaving first and second ramps on corresponding first and second sides ofan axis projecting radially outward from the center of the attachmentstructure through the circumferential center of the projection, eachprojection having a convex face, wherein each projection is asymmetricwith respect to the axis.
 16. A system according to claim 15, whereinthe member is made substantially of thermoplastic.
 17. A systemaccording to claim 15, wherein the member projections and the receptacleprojections interact in a plane substantially transverse to the verticalaxis of the member.
 18. A system according to claim 15, wherein themember rotates less than one-half full turn when engaging with thereceptacle.
 19. A system according to claim 15, wherein the memberrotates less than one-half full turn when disengaging from thereceptacle.
 20. An attachment system according to claim 15 for footwear,wherein the member is a cleat, the system comprising: A. a cleatreceptacle, the receptacle having an opening and a cleat engagingstructure including at least three receptacle projections; and B. arotationally attachable cleat having a vertical axis with first andsecond ends, including: i. at the second end, a surface engaging member;and ii. at the first end, an attachment structure including at leastthree cleat projections, each cleat projection having first and secondramps on corresponding first and second sides of an axis projectingradially outward from the center of the attachment structure through thecircumferential center of the projection, each projection having aconvex face, wherein each projection is asymmetric with respect to theaxis.
 21. A system according to claim 20, wherein the member projectionsinteract with the receptacle projections so that less force is requiredto engage the cleat with the receptacle than to disengage the cleat fromthe receptacle.
 22. A system according to claim 20, wherein the memberis made substantially of thermoplastic.
 23. A system according to claim20, wherein the member projections and the receptacle projectionsinteract in a plane substantially transverse to the vertical axis of themember.
 24. A system according to claim 20, wherein the member rotatesless than one-half full turn when engaging with the receptacle.
 25. Asystem according to claim 20, wherein the member rotates less thanone-half full turn when disengaging from the receptacle.
 26. A systemaccording to claim 20, wherein, as the member is installed into thereceptacle, each member projection has a rotationally leading edge and arotationally trailing edge, each receptacle projection engaging therotationally trailing edge of an installed member so as to resistloosening rotation of the cleat.
 27. A rotationally attachable cleat forfootwear having a vertical axis with first and second ends, the cleatcomprising: at the first end, a surface engaging member; and at thesecond end, an attachment structure including at least three cleatprojections, each cleat projection having first and second ramps oncorresponding first and second sides of an axis projecting radiallyoutward from the center of the attachment structure through thecircumferential center of the projection, each projection having aconvex face, wherein each projection is asymmetric with respect to theaxis, wherein the cleat projections are capable of interacting with acorresponding cleat receptacle.
 28. A cleat according to claim 27wherein less force is required to engage the cleat with the receptaclethan to disengage the cleat from the receptacle.
 29. A cleat accordingto claim 27, wherein the cleat is made substantially of thermoplastic.30. A cleat according to claim 27, wherein the cleat projections arecapable of interacting with the receptacle in a plane substantiallytransverse to the vertical axis of the cleat.
 31. A cleat according toclaim 27, wherein the cleat rotates less than one-half full turn whenengaging with the receptacle.
 32. A cleat according to claim 27, whereinthe cleat rotates less than one-half full turn when disengaging from thereceptacle.
 33. An attachment system, comprising: A. a receptacle, thereceptacle having an opening and a member engaging structure includingat least three receptacle projections; and B. a member, rotationallyattachable to the receptacle, having a vertical axis with first andsecond ends, including at the first end, an attachment structureincluding at least three member projections, each member projectionhaving first and second ramps on corresponding first and second sides ofan axis projecting radially outward from the center of the attachmentstructure through the circumferential center of the projection, eachprojection having a convex face, wherein the first and second ramps ofeach member projection interact with a corresponding receptacleprojection to resist rotation of the member relative to the receptacle.34. A system according to claim 33, wherein the member is madesubstantially of thermoplastic.
 35. A system according to claim 33,wherein the member projections and the receptacle projections interactin a plane substantially transverse to the vertical axis of the member.36. A system according to claim 33, wherein the member rotates less thanone-half full turn when engaging with the receptacle.
 37. A systemaccording to claim 33, wherein the member rotates less than one-halffull turn when disengaging with the receptacle.